Soil Phosphorus

AUS-TSR-CON-SOP General Moderate confidence

Benchmark Value

100 mg/kg
Direction: Higher is desirable ↑
Form: Point

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context. The scoring engine uses 2 benchmarks together — the Point form drives the primary score, while 1 guard(s) constrain the result.

Contributing Benchmarks

Point Primary MaximumOnly Guard

Evidence & Context

The Mt Spec site provides a directly measured Olsen P value of ~100 mg/kg.

Metric Definition:

Available Phosphorus: This measures the fraction of phosphorus that is readily available for plant uptake.

Benchmark Definition:

This benchmark represents the available phosphorus fraction readily available for plant uptake at the Mt Spec site in Australian tropical and subtropical rainforests.

Justification:

This is a high value, potentially reflecting the specific ecosystem's highly efficient P cycling and the nature of the Olsen extraction method in that particular soil matrix.

Sources (1)

Preview of Plant-soil nutrient relationships in the wet tropical rainforests of north Queensland, Australia (Maycock 1998)
Plant-soil nutrient relationships in the wet tropical rainforests of north Queensland, Australia (Maycock 1998) Journal

Plant-soil nutrient relationships in the wet tropical rainforests of north Queensland, Australia (Maycock 1998)

View Source

Supporting Sources (1)

Additional references from the underlying research that informed this benchmark.

Preview of Nutrient relationships of tree species in a New South Wales Subtropical rainforest (Turner & Lambert 1990)
Nutrient relationships of tree species in a New South Wales Subtropical rainforest (Turner & Lambert 1990)
Contextual Support GreyLiterature

Tool 2.8: Soil nutrient critical limits (Meat & Livestock Australia 2020)

View Source

Context

  • Region Australia
  • Biome Tropical & Subtropical Rainforests
  • Land Use Conservation / Protected Natural Areas
  • Assessment Pristine Reference
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 2
  • Effective From 25 Mar 2026

Notes

This category presents the most complex data. The Mt Spec site provides a directly measured Olsen P value of ~100 mg/kg.

Related Benchmarks

Other benchmarks in the AUS-TSR-CON-SOP family.

— mg/kg Moderate
Conservation / Protected Natural Areas · Pristine Reference
OptimalRange Active v1
3030 mg/kg Moderate
Conservation / Protected Natural Areas · Pristine Reference
Point Active v1
— mg/kg Moderate
Conservation / Protected Natural Areas · Pristine Reference
OptimalRange Active v1
10 mg/kg Moderate
Conservation / Protected Natural Areas · Pristine Reference
MinimumOnly Active v1
20 mg/kg Moderate
Conservation / Protected Natural Areas · Pristine Reference
MaximumOnly Active v1
60 mg/kg Moderate
Conservation / Protected Natural Areas · Pristine Reference
MaximumOnly Active v1
1300 mg/kg Moderate
Conservation / Protected Natural Areas · Pristine Reference
Point Superseded v1